Cisco Firepower Threat Defense Software SSL/TLS URL Category Bypass Vulnerability

A vulnerability in the Transport Layer Security version 1.3 (TLS 1.3) policy with URL category functionality for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass a configured TLS 1.3 policy to block traffic for a specific URL.

The vulnerability is due to a logic error with Snort handling of the connection with the TLS 1.3 policy and URL category configuration. An attacker could exploit this vulnerability by sending crafted TLS 1.3 connections to an affected device. A successful exploit could allow the attacker to bypass the TLS 1.3 policy and access URLs that are outside the affected device and normally would be dropped.

There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ssl-bypass-O5tGum2n [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ssl-bypass-O5tGum2n”]